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Search results for: gel-fraction, physico-mechanical properties, sem
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Evaluation and rationale of the performance of several elastomeric composites incorporating devulcanized EPDM
Publicationthylene Propylene Diene rubber (EPDM), is present in many applications. However, its crosslinked structure makes difficult its recycling. The use of devulcanized EPDM, (dEPDM) as a component of elastomeric composites, is a real possibility to reuse EPDM scraps. In this study, three matrices (natural rubber (NR), styrene butadiene rubber (SBR) and EPDM rubber) have been tested including devulcanized EPDM as a recycled component....
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Electrophoretic Deposition and Characterization of Chitosan/Eudragit E 100 Coatings on Titanium Substrate
PublicationCurrently, a significant problem is the production of coatings for titanium implants, which will be characterized by mechanical properties comparable to those of a human bone, high corrosion resistance, and low degradation rate in the body fluids. This paper aims to describe the properties of novel chitosan/Eudragit E 100 (chit/EE100) coatings deposited on titanium grade 2 substrate by the electrophoretic technique (EPD). The deposition...
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Tensile test of 1.4571 / X6CrNiMoTi17-12-2 / AISI 316Ti grade austenitic steel
Open Research DataShip structures and their components are build mainly of steel. Hull steel is used to build the hull structure. Some structural elements, such as RSW (Refrigerated See Water) tanks, or LNG (Liquid Natural Gas) tanks - gas transported at temperatures below -162° C, are build from austenitic steels. Austenitic steels have a different microstructure and...
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Dew and hoarfrost frequency, formation efficiency and chemistry in Wroclaw, Poland
PublicationThis article presents the results of a research study concerning a comparison of frequency, formation efficiency and basic physico-chemical properties of dew and hoarfrost in urban conditions. Longer than two-year series of measurements was carried out from 1 February 2008 to 10 March 2010 in Wroclaw, Poland. Sampling of atmospheric deposits was made by means of insulated plain passive radiative condensers, which allowed to collect...
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Durability evaluation of technical fabrics
PublicationA thorough examination of the influence of the conditions of use on the mechanical properties of technical fabrics is proposed. Laboratory experiments (uniaxial tensile, rheological, cyclic and biaxial tensile tests) have been conducted and the material’s parameters for Finite Element Method (FEM) simulations have been identified. Various constitutive models of technical fabrics are investigated and compared. On the basis of these...
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Functional properties of packaging materials from chemical modified stach.
PublicationThis work is focused on study of the mechanical and barrier properties of films obtained from potato starch modified with sodium tetrahydroxozincate generated in situ. The results show that the chemical modification of starch improved the water vapor permeability by about 25%, unfortunately decreased the elongation at break by 60%, when compared with unmodified starch films. However, placitization of films with glycerol at a concentration...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublicationStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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Effect of pulse laser treatment at different process variables on mechanical behavior of carbon nanotubes electrophoretically deposited on titanium alloy
PublicationPurpose: Titanium and its alloys are widely used as biomaterials for long-term implants, but they are usually surface-modified due to their weak bioactivity and wear resistance. Laser processing was used to modify the surface layer, and elemental carbon was a component of the deposited coatings. This research aims to use a combination of both methods based on preliminary electrophoretic deposition of multi-wall carbon nanotubes...
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Fire-Retardant Flexible Foamed Polyurethane (PU)-Based Composites: Armed and Charmed Ground Tire Rubber (GTR) Particles
PublicationInadequate fire resistance of polymers raises questions about their advanced applications. Flexible polyurethane (PU) foams have myriad applications but inherently suffer from very high flammability. Because of the dependency of the ultimate properties (mechanical and damping performance) of PU foams on their cellular structure, reinforcement of PU with additives brings about further concerns. Though they are highly flammable and...
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Właściwości złączy różnoimiennych stopu niklu Incoloy 800H ze stalą odporną na korozję 316L
PublicationW artykule przedstawiono problemy związane z wykonywaniem połączeń różnoimiennych typu Incoloy 800HT – austenityczna stal odporna na korozję 316L. Wykonano badania nieniszczące oraz niszczące, których wyniki pozwoliły na weryfikacje jakości wykonanych złączy próbnych. Nie stwierdzono występowania niezgodności spawalniczych oraz uzyskano wysokie właściwości wytrzymałościowe złączy. Badania metalograficzne ujawniły poprawne struktury...
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Koncepcja i analiza sensora/aktuatora piezoelektrycznego do pomiaru procesu starzenia się ludzkiej skóry
PublicationNiniejszy artykuł przedstawia nową koncepcję piezoelektrycznego sensora/aktuatora przeznaczonego do pomiaru właściwości mechanicznych tkanek miękkich a w szczególności skóry ludzkiej. Wyjaśnione jest analityczne podejście z wykorzystaniem schematu zastępczego Mason’a określającego aktuator w stanie rezonansu oraz opis metody impedancji elektromechanicznej wykorzystanej w systemie pomiarowym. Analiza z użyciem metody elementów...
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The Effect of Sodium Tetrafluoroborate on the Properties of Conversion Coatings Formed on the AZ91D Magnesium Alloy by Plasma Electrolytic Oxidation
PublicationMagnesium and its alloys are widely used in many areas because of their light weight, excellent dimensional stability, and high strength-to-weight ratio. However, the material exhibits poor wear and corrosion resistance, which limits its use. Plasma electrolytic oxidation (PEO) is an effective surface modification method for producing ceramic oxide layers on Mg and their alloys. The influence of the additions of sodium tetrafluoroborate...
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Antibacterial properties of laser-encapsulated titanium oxide nanotubes decorated with nanosilver and covered with chitosan/Eudragit polymers
PublicationTo provide antibacterial properties, the titanium samples were subjected to electrochemical oxidation in the fluoride-containing diethylene glycol-based electrolyte to create a titanium oxide nanotubular surface. Afterward, the surface was covered by sputtering with silver 5 nm film, and the tops of the nanotubes were capped using laser treatment, resulting in an appearance of silver nanoparticles (AgNPs) of around 30 nm in diameter...
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Active Polylactide-poly(ethylene glycol) Films Loaded with Olive Leaf Extract for Food Packaging—Antibacterial Activity, Surface, Thermal and Mechanical Evaluation
PublicationAs the demand for sustainable and innovative solutions in food packaging continues to grow, this study endeavors to introduce a comprehensive exploration of novel active materials. Specifically, we focus on characterizing polylactide-poly(ethylene glycol) (PLA/PEG) films filled with olive leaf extract (OLE; Olea europaea) obtained via solvent evaporation. Examined properties include surface structure, thermal degradation and mechanical...
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Up-conversion white emission and other luminescence properties of a YAG:Yb2O3·Tm2O3·Ho2O3@SiO2 glass-nanocomposite
PublicationWe report on a glass-nanocomposite material consisting of yttrium aluminum garnet (Y3Al5O12, YAG) nanocrystals co-doped with Yb3+, Tm3+ and Ho3+ ions as well as entrapped into a SiO2 xerogel. This 94YAG·5Yb2O3·0.8Tm2O3·0.2Ho2O3@SiO2 (abbr. YAG:YbTmHo@SiO2) nanocomposite material has been prepared by sol–gel procedure. Its structure and morphology has been characterized by means of X-ray diffraction (XRD) and scanning electron microscope...
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The role of bile salts in digestion
PublicationBile salts (BS) are bio-surfactants present in the gastrointestinal tract (GIT) that play a crucial role in the digestion and absorption of nutrients. The importance of BS for controlled release and transport of lipid soluble nutrients and drugs has recently stimulated scientific interest in these physiological compounds. BS are so-called facial amphiphiles showing a molecular structure that is very distinct from classical surfactants....
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Novel Approaches of Using of Spirulina Platensis in Natural Rubber Based Composites
PublicationThe aim of this work was to investigate the influence of Spirulina (Spirulina platensis) as a natural filler on the curing characterization, morphology and mechanical, thermomechanical and thermal properties of natural rubber (NR) based composites. Spirulina was introduced into NR mixture in amount of 0 phr, 10 phr and 30 phr. The vulcanization process was carried out at the determined process condition by using hydraulic press...
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Wpływ azotowania jarzeniowego i laserowego nadtapiania na odporność kawitacyjną stali X5CrNi18-10
PublicationNierdzewne stale austenityczne charakteryzują się doskonałą odpornością korozyjną, aczkolwiek niskimi właściwościami mechanicznymi. W wielu przypadkach ogranicza to ich eksploatację w warunkach przemysłowych. Ponadto, nierdzewne stale austenityczne są wrażliwe na korozję lokalną w obecności jonów halogenkowych. Technologie materiałowe, które dają potencjalne możliwości otrzymywania korzystnego wpływu na właściwości mechaniczne...
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Synthesis and Characterization of Poly(zwitterionic) Structures for Energy Conversion and Storage
PublicationZwitterions are unique class of molecules that possess two functional groups bearing electric charges, one positive and second negative. This setup results in peculiar properties such as high water retention and anti-fouling capability. Therefore, zwitterionic coatings and gels are commonly applied in e.g. biosensing and bioelectronic devices. Despite those applications, there are other perspectives for zwitterionic materials....
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Application of Artificial Neural Networks to Predict Insulation Properties of Lightweight Concrete
PublicationPredicting the properties of concrete before its design and application process allows for refining and optimizing its composition. However, the properties of lightweight concrete are much harder to predict than those of normal weight concrete, especially if the forecast concerns the insulating properties of concrete with artificial lightweight aggregate (LWA). It is possible to use porous aggregates and precisely modify the composition...
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Properties of Nanohydroxyapatite Coatings Doped with Nanocopper, Obtained by Electrophoretic Deposition on Ti13Zr13Nb Alloy
PublicationNowadays, hydroxyapatite coatings are the most common surface modification of long-term implants. These coatings are characterized by high thickness and poor adhesion to the metallic substrate. The present research is aimed at characterizing the properties of nanohydroxyapatite (nanoHAp) with the addition of copper nanoparticle (nanoCu) coatings deposited on the Ti13Zr13Nb alloy by an electrophoresis process. The deposition of...
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Thermoplastic elastomer filaments and their application In 3D printig
PublicationThe paper provides an overview on the materials used in the 3D printing technology (the Polish and foreign market) with a particular focus on flexible filaments and their possible application in the industry. There are described the techniques of 3D printing and modern filaments available on the market. There is observed the increase of interest in the production of products from filaments based on thermoplastic elastomers (TPE),...
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Interrelated shape memory and Payne effect in polyurethane/graphene oxide nanocomposites
PublicationWe report the fabrication of graphene oxide (GO) based polyurethane (PU) nanocomposites by a simple method of mixing and their shape memory properties at different temperatures. Both the polymer and the filler were synthesized in the laboratory by simple and easy methods – PU by pre-polymer method and GO by improved graphene oxide synthesis method. High molecular level dispersion of GO platelets within the PU matrix and thus good...
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Influence of Heat Treatment Temperature on Fatigue Toughness in Medium-Carbon High-Strength Steels
PublicationCurrent research has demonstrated that the tempering temperature affects the martensitic transformation of medium-carbon high-strength steels. This temperature plays an important role in the final microstructure, percentage ratios of martensite to ferrite phases and, consequently, in the mechanical properties and the fatigue response. So far, the relationship between the martensitic tempering temperature and the cyclic deformation...
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Thermoplastic polyurethane/(organically modified montmorillonite) nanocomposites produced by in situ polymerization
PublicationA series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with different hard segment ratios) and two types of organically modified montmorillonites (OMMT) - Cloisite® 10A and Cloisite® 20A. The thermal behavior was examined by non-isothermal thermogravimetry (TG, DTG), Differential Scanning Calorimetry (DSC) and Dynamic-Mechanical Thermal Analysis (DMTA). The results of X-ray analyses showed that...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublicationThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Cavitation Erosion Resistance Influence of Material Properties
PublicationThe cavitation erosion is the phenomena that causes degradation of fluid flow machinery components due to repetitive implosion of cavitation bubbles adjacent to the solid surface. Cavitation erosion is a complex phenomenon, which includes not only hydrodynamic factors of liquid, but also properties of erodible material e.g. microstructure, hardness or Young modulus. In order to reduce the negative impact of erosion on machine components,...
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Design and simulation of a new prototype of piezoelectric cantilever sensor/actuator for analysis of the soft tissues properties
PublicationThis paper is devoted to a new prototype of piezoelectric cantilever transducer dedicated for the characterization of the mechanical properties of soft tissues. General description of the actuator’s structure is presented including the basic principles of the measurement. The chosen geometry of the prototype is discussed and compared with the existing one. Constitutive equations are presented for the active and passive layer of...
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A new prototype of piezoelectric bending resonant transducer for analysis of soft tissues properties
PublicationThis paper is devoted to a new piezoelectric bending resonant transducer prototype dedicated to the characterization of the mechanical properties of soft tissue. A general description of the actuator’s structure is presented including the basic principles of the measurement. The chosen geometry of the prototype is discussed and compared with the existing version. Constitutive equations are presented for the active and passive layer...
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Finite element simulation of cross shaped window panel supports
PublicationThe aim of the work is to verify suitability of cross-shaped window panel supports for mullion-transom wall systems. The Finite Element Method (FEM) is chosen to determine the behaviour of stainless steel elements under loading. The advanced non-linear numerical simulations are carried out using an implicit FEM software package MSC.Marc. This study is proposed to initiate the comprehensive investigation of mechanical properties...
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Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublicationThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
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The inhibition effect of mad Honey on corrosion of 2007-type aluminium alloy in 3.5% NaCl solution
PublicationThe inhibition effect of mad honey on corrosion of 2007-type aluminium alloy in 3.5% NaCl solution was investigated by Tafel extrapolarisation (TP), electrochemical impedance spectroscopy (EIS) and dynamic electrochemical impedance spectroscopy (DEIS). All the studied parameters exhibited good anti-corrosive properties against corrosion of 2007-type aluminium alloy in the test solution; the corrosion rates decreased with the increase...
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Microstructure–Property Relationship of Polyurethane Foams Modified with Baltic Sea Biomass: Microcomputed Tomography vs. Scanning Electron Microscopy
PublicationIn this paper, novel rigid polyurethane foams modified with Baltic Sea biomass were compared with traditional petro-based polyurethane foam as reference sample. A special attention was focused on complex studies of microstructure, which was visualized and measured in 3D with high-resolution microcomputed tomography (microCT) and, as commonly applied for this purpose, scanning electron microscopy (SEM). The impact of pore volume,...
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Dropping Knowledge on Space Tribology: Insights into the Effects of Microgravity on Solid Lubricants from the Bremen Tower Drop Experiment
PublicationThe performance of space mechanisms, such as satellite solar panels, hinges, and robotic arms, heavily relies on the tribological properties of the lubricants used in their design. Their mechanical properties can be significantly affected by the extreme conditions of outer space: including high vacuum, absence of oxygen, and extreme temperatures among others. However, due to technical challenges, the effects of microgravity on...
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Experimental and Quantum Chemical Evaluation of 8-Hydroxyquinoline as a Corrosion Inhibitor for Copper in 0.1 M HCl
PublicationThe corrosion inhibition properties of 8-hydroxyquinoline (8-HQ) in 0.1 M HCl for copper have been investigated by using experimental (electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS), and potentiodynamic polarization) and theoretical methods complemented by surface morphological examination with the aid of scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy...
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Core-Shell Nanoparticles with Hyperbranched Poly(arylene-oxindole) Interiors
PublicationCore-shell type star polymers composed of poly(tert-butyl acrylate) (poly(t-BuA)) arms and 100% hyperbranched poly(arylene-oxindole) interiors were synthesized via the "core-first" method. Atom transfer radical polymerization of t-BuA initiated by 2-bromopropionyl terminal groups of the hyperbranched core was applied for the synthesis of the stars. The resultant star structures were characterized by gel permeation chromatography...
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Structural and optical investigations of sol-gel derived lithium titanate thin films
Publicationin this paper structural and optical studies of lithium titanate (lto) thin films are presented. nanocrystalline thin films with 800 nm thickness were prepared by sol-gel method. to examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at 550 °c for 10, 20 and 80 h. structure of manufactured thin films was investigated using x-ray diffraction (xrd). the most visible lithium titanate...
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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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Bacterial cellulose in the field of wound healing and regenerative medicine of skin: recent trends and future prospectives
PublicationIn this overview, we focused on the bacterial cellulose (BC) applications, described in recently published scientific papers, in the field of skin regenerative medicine and wound care industry. Bacterial cellulose was proven to be biocompatible with living tissues. Moreover, its mechanical properties and porous structure are considered to be suitable for biomedical applications. It is due to the fact that porous structure of bacterial...
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Bio-Based Polyurethane Composites and Hybrid Composites Containing a New Type of Bio-Polyol and Addition of Natural and Synthetic Fibers
PublicationThis article describes how new bio-based polyol during the liquefaction process can be obtained. Selected polyol was tested in the production of polyurethane resins. Moreover, this research describes the process of manufacturing polyurethane materials and the impact of two different types of fibers—synthetic and natural (glass and sisal fibers)—on the properties of composites. The best properties were achieved at a reaction temperature...
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Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
PublicationThe Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical...
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The Green Approach to the Synthesis of Bio-Based Thermoplastic Polyurethane Elastomers with Partially Bio-Based Hard Blocks
PublicationBio-based polymeric materials and green routes for their preparation are current issues of many research works. In this work, we used the diisocyanate mixture based on partially bio-based diisocyanate origin and typical petrochemical diisocyanate for the preparation of novel bio-based thermoplastic polyurethane elastomers (bio-TPUs). We studied the influence of the diisocyanate mixture composition on the chemical structure, thermal,...
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Polyester sail technical woven fabric behaviour under uniaxial and biaxial tensile tests
PublicationThe paper is focused on the identification of mechanical properties of a sail technical woven fabric (yacht sailcloth polyester) style 480 AP with MTO (Medium Tempered Optimized) finish. The non-linear elastic behaviour of the fabric applied for sails is investigated under uniaxial and biaxial tensile tests. Comparison of non-linear elastic parameters with others polyester coated fabrics is made. This paper is intended to be an...
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Sea bottom structure investigation by means of acoustic methods
PublicationThe main aim of the paper is the result of experimental investigations of the seabed in the Gulf of Gdańsk arried out using parametric echosounder as a main measuring tool. Examination of the surface's upper layer of the seabed, especially is acoustic properties, reflecting most often transsmision and reflection properties of the incident elastic wave, could be a valuable material for determination of the stratification, and the...
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Sensitivity analysis of free torsional vibration frequencies of thin-walled laminated beams under axial load
PublicationThe paper addresses sensitivity analysis of free torsional vibration frequencies of thin-walled beams of bisymmetric open cross-section made of unidirectional fibre-reinforced laminate. The warping effect and the axial end load are taken into account. The consideration is based upon the classical theory of thin-walled beams of non-deformable cross-section. The first-order sensitivity variation of the frequencies is derived with...
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Validation of atmospheric aerosols sampling in equivalent fractions
PublicationPhysical properties and chemical composition of atmospheric aerosols are of extreme importance, in many fields of interest, namely the Environment even with legal implications. Atmospheric sampling poses inherent problems with consequent demands on sampling optimisation, with sampling strategies requiring validation. In this work a study was conducted aiming at validating the collection of atmospheric aerosols in equivalent fractions....
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Mitigating metal-organic framework (MOF) toxicity for biomedical applications
PublicationMetal-organic frameworks (MOFs) are a novel class of crystalline porous materials, consisting of metal ions and organic linkers. These hybrid materials are highly porous and have a large specific surface area, making them of great interest for applications in gas separation, energy storage, biomedical imaging, and drug delivery. As MOFs are being explored for biomedical applications, it is essential to comprehensively assess their...
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Sludge Treatment Reed Beds (STRBs) as a Eco-solution of Sludge Utilization for Local Wastewater Treatment Plants
PublicationSewage sludge is a by-product of wastewater treatment processes. In Poland, the amout of sewage sludge has been still growing in recent years, due to inhencement of pollutants removal in wastewater treatment plants (WWTPs). One of the systems used to transform sewage sludge into fertilizer is a technology called Sludge Treatment Reed Beds (STRBs). Reed systems are periodically irrigated with sewage sludge with a low dry matter...
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An attempt to mechanistically explain the viscoelastic behavior of transparent epoxy/starch-modified ZnO nanocomposite coatings
PublicationThe effects of bare and starch-modified ZnO (ZnO-St) nanoparticles on viscoelastic and mechanical properties are studied by dynamic mechanical and tensile analyses. Transparent epoxy-based nanocomposite films are prepared by incorporating bare or starch-modified ZnO particles into the epoxy matrix. The results demonstrated that ZnO particles hindered the curing reactions and hence the final properties of the cured epoxy. As a result,...
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Growth and Isolation of Large Area Boron‐Doped Nanocrystalline Diamond Sheets: A Route toward Diamond‐on‐Graphene Heterojunction
PublicationMany material device applications would benefit from thin diamond coatings, but current growth techniques, such as chemical vapor deposition (CVD) or atomic layer deposition require high substrate and gas‐phase temperatures that would destroy the device being coated. The development of freestanding, thin boron‐doped diamond nanosheets grown on tantalum foil substrates via microwave plasma‐assisted CVD is reported. These diamond...